1. Field of the Invention
The present invention relates to a pair of soft-shell connectors (which consist of a male one and a female one) enabling a user to check to see if the connectors are precisely connected with each other (hereinafter referred to as the connection-condition checkable connectors).
2. Description of the Prior Art
For example, ones of conventional soft-shell connectors of this kind, i.e., conventional connection-condition checkable connectors are shown in FIG. 1, which are disclosed in detail in Japanese Patent Laid-Open No. Sho 63-225480.
Such conventional checkable connectors consist of a male one 1 and a female one 3. The male connector 1 is provided with at least one female contact (not shown), while the female connector 3 is provided with at least one male contact (not shown). The male connector 1 has a housing 5 provided with a lock arm 9. The lock arm 9 is, as shown in FIG. 2, provided with a projection 7 forming a part of a locking mechanism of the connectors. On the other hand, the female connector 3 has a hood 11 provided with a counter projection 13 which forms the remaining part of the locking mechanism of the connectors.
In the male connector 1, a plurality of detection marks 15 (each of which assumes a convex shape in cross section as shown in FIG. 2) are integrally formed with a rear-end portion 9a of the lock arm 9 so as to be disposed on the portion 9a at equal intervals along a longitudinal direction of the lock arm 9.
On the other hand, on an upper surface of the hood 11 of the female connector 3 are integrally formed a plurality of detection marks 17 each of which assumes the same form as that of each of the detection marks 15 of the male connector 1.
In checking operation of the detection marks 15 and 17, a detecting unit such as a photosensor and the like (which is provided with a photo-emitter portion and a photo-receiver portion) for detecting arrangement of the detection marks 15 and 17 is used. In operation, the detecting unit detects the arrangement of these marks 15 and 17 to issue an arrangement signal to a computer of the detecting unit. In the computer of the unit, the signal thus issued from the unit is first converted into a detected pattern and then compared with a predetermined reference pattern stored in the computer, so that the computer determines whether or not the detected pattern is coincident with the reference pattern to enable the unit to determine whether or not the projection 7 of the lock arm 9 of the male connector 1 is completely engaged with the counter projection 13 of the hood 11 of the female connector 3, i.e., to determine whether or not these male and female connectors are completely connected with each other.
In the conventional checkable connectors, however, after the connectors are completely connected with each other, a gap "a" is produced in the longitudinal direction of the lock arm 9 of the male connector 1 between the male connector 1 and the female connector 3, as shown in FIG. 2. Namely, in connecting operation of the connectors for inserting the male connector 1 into the female connector 3 to have a front end of the male connector 1 abut on an innermost end of the female connector 3 as shown in FIG. 2, the lock arm 9 is first resiliently deformed to move the projection 7 of the arm 9 to a position indicated in phantom line as shown in FIG. 3, and thereafter the projection 7 returns to its original position indicated in solid line (shown in FIG. 3) through a curved path indicated by an arrow shown in FIG. 3.
Due to such curved path of the projection 7 in the female connector 3, the presence of the gap "a" between the connectors having been connected with each other is inevitable. Consequently, in the thus connected connectors, as is clear from FIG. 4, the gap "a" may be produced between the front end of the male connector 1 and the innermost end of the female connector 3. Due to the presence of such gap "a" in the connectors having been connected with each other, a space (in the longitudinal direction of the lock arm 9 of the male connector 1) between the detection mark 15 of the male connector 1 and the detection mark 17 of the female connector 3 varies in amount within a range of from d to (d+"a") as is clear from FIGS. 2 and 4, to make it difficult to precisely check the detection marks 15, 17. Therefore, in the conventional checkable connectors, there is a fear that the detecting unit issues a false alarm to the user even when the connectors are completely connected with each other.